1. Field of the Invention
The present invention relates to a process for preparing an optically active arylacetic acid derivative. More particularly, the present invention relates to a process for preparing an optically active arylacetic acid derivative useful as an intermediate for the preparation of medicines and agricultural chemicals.
2. Description of the Prior Art
It is known from U.S. Pat. No. 4,409,397 to use a catalyst of the formula: EQU LM(olefin).sub.2.sup.+ X.sup.- (V)
wherein M is a rhodium atom, a ruthenium atom or an iridium atom, L is an asymmetric ligand of ferrocenyl phosphine or pyridinyl phosphine, (olefin).sub.2 represents 2,5-norbornadiene or 1,5-cyclooctadiene, and X is ClO.sub.4, BF.sub.4 or PF.sub.6 in the preparation of optically active phenylacetic acid by asymmetric reduction with hydrogen. As ferrocenyl phosphine, disclosed in this patent is an optically active ferrocenyl phosphine of the formula: ##STR5## wherein R.sub.5 ' and R.sub.6 ' are each a lower alkyl group, a C.sub.5 -C.sub.8 cycloalkyl group, a phenyl group or a C.sub.5 -C.sub.6 heterocyclic group, Q is a lower alkyl group, an alkenyl group or a group of the formula: EQU C(R.sub.7 ')(R.sub.8 ')-Y'
wherein R.sub.7 ' and R.sub.8 ' are each a hydrogen atom, a lower alkyl group or an aryl group or together form a cycloalkyl group, and Y' is an hydrogen atom, a hydroxyl group, an acyloxy group or a group of the formula: EQU Z'(R.sub.10 ').sub.2 or PR.sub.10 'R.sub.11 '
wherein Z' is N, P, As or Sb, R.sub.10 ' and R.sub.11 ' are each a hydrogen atom or an alkyl group or (R.sub.10 ').sub.2 forms a heterocyclic group containing N or P in Z' and optionally additional N or O; and n is 0 (zero) or 1 (one).
The process for preparing the optically active phenylacetic acid derivative by using a metal catalyst modified with such optically active ferrocenyl phosphine compounds is not industrially satisfactory since it cannot necessarily produce the desired compound in a high optical yield and conversion.